RD Sharma Class 9 Solutions Chapter 2 Exponents of Real Numbers
RD Sharma Class 9 Chapter 2 Exponents of Real Numbers Ex 2.1
Question 1.
Simplify the following:
Solution:
Question 2.
If a = 3 and b =-2, find the values of:
(i) a
a
+ b
b
(ii) a
b
+ b
a
(iii) (a+b)
ab
Solution:
Question 3.
Prove that:
Solution:
Question 4.
Prove that
Solution:
Question 5.
Prove that
Solution:
Question 6.
Solution:
Question 7.
Simplify the following:
Solution:
Question 8.
Solve the following equations for x:
Solution:
Question 9.
Solve the following equations for x:
Solution:
Question 10.
If 49392 = a
4
b
2
V
3
, find the values.of a, b and c, where a, b and c are different positive primes.
Solution:
Question 11.
If 1176 = 2
a
x 3
b
x T
c
, find a, 6 and c.
Solution:
Question 12.
Given 4725 = 3
a
5
b
7
c
, find:
(i) the integral values of a, b and c
(ii) the value of 2
-a
3
b
7
c
Solution:
Question 13.
If a = xy
p-1
, b = xy
q
-1
and c = xy
r-1
, prove that a
q-r
b
r-p
c
p-q
= 1
Solution:
RD Sharma Class 9 Solutions Chapter 2 Exponents of Real Numbers E x 2.2
Question 1.
Assuming that x, y, z are positive real numbers, simplify each of the following:
Solution:
Question 2.
Simplify:
Solution:
Question 3.
Prove that:
Solution:
Question 4.
Show that:
Solution:
Question 5.
Solution:
Question 6.
Solution:
Question 7.
Solution:
Question 8.
Solution:
Question 9.
Solution:
Question 10.
Find the values of x in each of the following:
Solution:
Question 11.
If x = 2
1
/3
+ 2
2/3
, show that x
3
– 6x = 6.
Solution:
Question 12.
Determine (8x)
x
, if 9
x
+ 2
= 240 + 9
x
.
Solution:
Question 13.
If 3
x
+
1
= 9
x-
2
, find the value of 2
1 +x
.
Solution:
Question 14.
If 3
4x
= (81)
-1
and 10
1/y
= 0.0001, find the value of 2
-x+4y
Solution:
Question 15.
If 5
3x
= 125 and 10
y
= 0.001 find x and y.
Solution:
Question 16.
Solve the following equations:
Solution:
Question 17.
Solution:
Question 18.
If a and b are different positive primes such that
Solution:
Question 19.
If 2
x
x 3
y
x 5
z
= 2160, find x, y and z. Hence, compute the value of 3
x
x 2
-y
x 5
-z
.
Solution:
Question 20.
If 1176 = 2
a
x 3
b
x 7
c
, find the values of a, b and c. Hence, compute the value of 2
a
x 3
b
x 7
-c
as a fraction.
Solution:
Question 21.
Simplify:
Solution:
Question 22.
Show that:
Solution:
Question 23.
Solution:
RD Sharma Class 9 Chapter 2 Exponents of Real Numbers VSAQS
Question 1.
Write (625)
–
1/4
in decimal form.
Solution:
Question 2.
State the product law of exponents:
Solution:
x
m
x x
n
= x
m +n
Question 3.
State the quotient law of exponents.
Solution:
x
m
÷ x
n
= x
m -n
Question 4.
State the power law of exponents.
Solution:
(x
m
)
n
=x
m x n
= x
mn
Question 5.
If 2
4
x 4
2
– 16
x
, then find the value of x.
Solution:
Question 6.
Solution:
Question 7.
Write the value of \(\sqrt [ 3 ]{ 7 }\) x \(\sqrt [ 3 ]{ 49 }\) .
Solution:
Question 8.
Solution:
Question 9.
Write the value of \(\sqrt [ 3 ]{ 125×27 }\)
Solution:
Question 10.
Solution:
Question 11.
Solution:
Question 12.
Solution:
Question 13.
Solution:
Question 14.
If (x – 1)
3
= 8, what is the value of (x + 1)
2
?
Solution:
Class 9 RD Sharma Solutions Chapter 2 Exponents of Real Numbers MCQS
Mark the correct alternative in each of the following:
Question 1.
The value of {2 – 3 (2 – 3)
3
}
3
is
(a) 5
(b) 125
(c) \(\frac { 1 }{ 5 }\)
(d) -125
Solution:
{2 – 3 (2 – 3)
3
}
3
= {2 – 3 (-1)
3
}
3
= {2 – 3 x (-1)}
3
= (2 + 3)
3
= (5)
3
= 125 (b)
Question 2.
The value of x – y
x-y
when x = 2 and y = -2 is
(a) 18
(b) -18
(c) 14
(d) -14
Solution:
x = 2, y = -2
x-y
x-y
= 2 – (-2)
2 – (-2)
= 2 – (-2)
2
+
2
= 2 – (-2)
4
= 2 – (+16) = 2 – 16 = -14 (d)
Question 3.
The product of the square root of x with the cube root of x, is
(a) cube root of the square root of x
(b) sixth root of the fifth power of x
(c) fifth root of the sixth power of x
(d) sixth root of x
Solution:
Question 4.
The seventh root of x divided by the eighth root of x is
Solution:
Question 5.
The square root of 64 divided by the cube root of 64 is
(a) 64
(b) 2
(c) \(\frac { 1 }{ 2 }\)
(d) 64
\(\frac { 2 }{ 3 }\)
Solution:
Question 6.
Which of the following is (are) not equal to
Solution:
Question 7.
When simplified (x
–
1
+ y
–
1
)
–
1
is equal to
Solution:
Question 8.
If 8
x
+1
= 64, what is the value of 3
2x
+1
?
(a) 1
(b) 3
(c) 9
(d) 27
Solution:
Question 9.
If (2
3
)
2
= 4
x
then 3
x
=
(a) 3
(b) 6
(c) 9
(d) 27
Solution:
Question 10.
If x
-2
= 64, then x
\(\frac { 1 }{ 3 }\)
+ x°=
(a) 2
(b) 3
(c) \(\frac { 3 }{ 2 }\)
(c) \(\frac { 2 }{ 3 }\)
Solution:
Question 11.
When simplified ( –\(\frac { 1 }{ 27 }\))
\(\frac { -2 }{ 3 }\)
(a) 9
(b) -9
(c) \(\frac { 1 }{ 9 }\)
(d) –\(\frac { 1 }{ 9 }\)
Solution:
Question 12.
Which one of the following is not equal to
Solution:
Question 13.
Which one of the following is not equal to
Solution:
Question 14.
If a, b, c are positive real numbers, then
Solution:
Question 15.
Solution:
Question 16.
Solution:
Question 17.
Solution:
Question 18.
Solution:
Question 19.
Solution:
Question 20.
Solution:
Question 21.
The value of {(23 + 2
2
)
2/3
+ (150 -29)
1/2
}
2
is
(a) 196
(b) 289
(c) 324
(d) 400
Solution:
{(23 + 2
2
)
2
/
3
+ (150 – 29)
1/2
}
2
= [(23×4)
\(\frac { 2 }{ 3 }\)
+(150 – 29)
\(\frac { 1 }{ 2 }\)
]
2
= [(27)
\(\frac { 2 }{ 3 }\)
+ (121)
\(\frac { 1 }{ 2 }\)
]
2
= [(3
3
)
3
+(11
2
)
\(\frac { 1 }{ 2 }\)
]
2
= (9 + 11)
2
= (20)
2
= 400 (d)
Question 22.
(256)
0.16
x (256)
0.09
(a) 4
(b) 16
(c) 64
(d) 256.25
Solution:
Question 23.
If 10
2y
= 25, then 10
-y
equals
Solution:
Question 24.
If 9
X
+
2
= 240 + 9
X
. then x =
(a) 0.5
(b) 0.2
(c) 0.4
(d) 0.1
Solution:
Question 25.
If x is a positive real number and x
2
= 2, then x
3
=
(a) \(\sqrt { 2 } \)
(b) 2\(\sqrt { 2 } \)
(c) 3\(\sqrt { 2 } \)
(d) 4
Solution:
Question 26.
Solution:
Question 27.
Solution:
Question 28.
Solution:
Question 29.
Solution:
Question 30.
Solution:
Question 31.
Solution:
Question 32.
Solution:
Question 33.
If (16)
2x + 3
= (64)
x + 3
, then 4
2x – 2
=
(a) 64
(b) 256
(c) 32
(d) 512
Solution:
Question 34.
Solution:
Question 35.
Solution:
Question 36.
Solution:
Question 37.
Solution:
Question 38.
Solution:
Question 39.
Solution:
Question 40.
Solution:
RD Sharma Class 9th Solutions Chapter 2 Exponents of Real Numbers Exercise 2.1